Facebook App ID/API Key - you can leave it empty
Facebook admins Id - you can leave it empty
When do You need a fb:app_id or fb:admins?
It's important for Domain Insights.
read the link https://developers.facebook.com/docs/platforminsights/domains
We recommend to use it.Follow Button
It's only for Follow Button
Facebook Name (for follow) - you can leave it empty
We tried to add a comment on out test site. We could add it, but after refreshing a page, we see empty "comment list"...
We asked Facebook about this bug...
Can you give me a URL for your test page?